MRI is an imaging method which excites nuclear spins of an object set m a static magnetic field with a magnetic field RF (radio frequency) signal having the Larmor frequency and reconstructs an image based on NMR (NMR: nuclear magnetic resonance) signals generated due to the excitation.
In an MRI examination, image data is often acquired from an area that is the same as that used for acquisition of image data in the past. Specifically acquisition conditions of image data are set with reference to imaging conditions of image data acquired in the past. More specifically, the same imaging conditions, including a slice thickness, the number of slices and a slice angle, as past conditions can be set for imaging assuming that a position of an object is constant in an apparatus coordinate system.
[Prior Technical Literature]    [Patent literature 1] JPA 2007-167634
In an MRI apparatus, uniformity in the magnetic field decreases at a position further from the center of the static magnetic field. Therefore, there is a problem that an image data quality at a slice position far from the magnetic field center may be deteriorated. Especially, if a part of the highest interest is far from the magnetic field center in a case of acquiring image data repeatedly from a same imaging area, image data having a deteriorated image quality is acquired repeatedly because the same imaging area is repeatedly set constantly.
It is an object of the present invention to provide a magnetic resonance imaging apparatus, a magnetic resonance imaging method and a medical system which can acquire image data of a part of high interest repeatedly with an improved image quality.